# QSFP28 Passive Cable Overview and Applications

## Introduction to QSFP28 Passive Cable

The QSFP28 passive cable is a high-speed interconnect solution designed for data centers and high-performance computing environments. As a passive copper cable, it does not require signal amplification or retiming, making it a cost-effective option for short-range connections.

## Key Features of QSFP28 Passive Cables

1. High-Speed Performance

QSFP28 passive cables support data rates up to 100Gbps (4x25Gbps), making them ideal for modern high-bandwidth applications.

2. Low Power Consumption

Unlike active optical cables, passive copper cables consume minimal power since they don’t require signal processing electronics.

3. Cost-Effective Solution

Passive cables offer significant cost savings compared to active optical solutions for short-reach applications.

4. Plug-and-Play Installation

These cables require no configuration and are ready to use upon connection.

## Common Applications of QSFP28 Passive Cables

Data Center Interconnects

QSFP28 passive cables are widely used in data centers for:

• Top-of-rack (ToR) switch to server connections
• Intra-rack connections
• Short-distance switch-to-switch links

High-Performance Computing

These cables are essential in HPC environments where high-speed, low-latency connections are required between compute nodes.

Storage Area Networks

QSFP28 passive cables provide reliable connections between storage arrays and servers in SAN environments.

## Distance Limitations and Considerations

While QSFP28 passive cables offer excellent performance, they are typically limited to distances of 3-5 meters due to signal integrity constraints. For longer distances, active optical cables or transceivers with fiber optics may be more appropriate.

## Choosing the Right QSFP28 Passive Cable

When selecting a QSFP28 passive cable, consider:

• Required cable length
• Operating temperature range
• Bend radius requirements
• Compatibility with your networking equipment

## Future of QSFP28 Technology

As data rates continue to increase, QSFP28 passive cables remain a viable solution for short-reach applications. The technology is expected to evolve with improved materials and designs to support even higher data rates while maintaining cost-effectiveness.